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Free PHP scripts with support forums, including Contact Form, Daily Pic, Gallery Generator, Mailing List, Random Popup, Simple Gallery, Simple Member, ...

http://php.resourceindex.com/Complete_Scripts
PHP scripts of all varieties that are ready for use on your web site.

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PHP scripts - download free PHP scripts from PHPJunkyard.

http://www.scriptdungeon.com/php_scripts.php
Free PHP Scripts available for download. Browse categories to find free php scripts and resources.